Bone anchors for attaching suture, bone and/or tissue to bone are well known in the art. Also well known are inserter tools for deploying such bone anchors in bone. Examples of such devices may be seen in U.S. Pat. Nos. 4,898,156; 4,899,743; 4,946,468; 4,968,315; 5,002,550; 5,046,513; 5,192,303; 5,207,679; and 5,217,486; and in U.S. patent applications Ser. Nos. 07/981,011; 08/030,657; 08/075,168; 08/098,599; 08/180,425; 08/197,927; and 08/312,892.
While the bone anchor inserter tools disclosed in the foregoing U.S. patents and patent applications have proven satisfactory, it has been noted that certain problems arise from time to time when using such tools.
More particularly, the bone anchor inserters of the prior art typically include a sleeve open at a distal end. In loading an anchor into the sleeve, the anchor is pushed through the open end of the sleeve and into the sleeve. See, for example, the above-identified U.S. patent application Ser. No. 08/312,892. Given the small dimensions of the anchors and sleeves involved, it is sometimes difficult to obtain the correct alignment of anchor and sleeve. Instead of the anchor being readily slipped into the sleeve, the anchor sometimes slips away and falls from the hand. Compounding the difficulty in some devices is the fact that many anchors are provided with barbs or the like. The barbs extend outwardly from the device and are pointed in such direction as to resist insertion into the open end of a sleeve.
In the above-identified U.S. patent application Ser. No. 08/312,894, there is disclosed an alternative loading arrangement wherein the anchor is inserted in a proximal end of a shaft. The shaft is discrete from the remainder of the inserter assembly. With the anchor in the shaft, the shaft is connected to the inserter assembly.
There is a need, in bone anchor inserters, for an easier and more reliable anchor loading facility. More particularly, there is a need for a bone anchor loading facility wherein an anchor may be readily loaded into an inserter shaft without having to disassemble and reassemble the inserter. There is further needed an improved method for loading a bone anchor into a bone anchor inserter, an improved method for holding and delivering a bone anchor, and an improved method for inserting a bone anchor in a bore in a bone.